Chemical modification of small molecules by microorganisms is commonly known as biotransformation or biological synthesis. There are extensive biotransformation researches for production of materials that can be utilized in the industries. Microbial production of alcohols, sugars or organic acids is a promising approach for obtaining final products or building-block chemicals from renewable carbon sources, e.g. monomers for polymer synthesis. Among the most common chemicals produced by a biotransformation process there are 1,3-propanediol, citric, lactic or succinic acid, and sugar alcohols, like mannitol. The biotechnological conversion of glycerol to 1,3-propanediol is commonly achieved by bacteria under anaerobic conditions.
Willke et al. (Eur. J. Lipid Sci. Technol. 2008, 110, 831-840) review the biotransformation of glycerol into 1,3-propanediol without using fossil resources. Microbes of the species Clostridiaceae, Enterobacteriaceae and Lactobacilli were reported to be promising candidates for industrial 1,3-propanediol production.
While microbial processes for the microbiological preparation of valuable chemicals from renewable resources are known, most of the used production organisms rely on one or a few carbon sources and most of the known production organisms require a high degree of purity of the carbon sources. Thus, the carbon source is a major cost factor.
It would be desirable to employ carbon containing raw or waste materials like raw glycerol, which is a by-product from biodiesel production, in such biotransformation processes. However, impurities generally inhibit production. Efficient use of such raw material in biotransformation processes has not been achieved so far.
Consequently, there is the need for the development of new platform organisms, exhibiting high productivity of desired substances, converting a wide range of carbon sources with a low degree of purity into desirable chemicals.
Lactobacilli have been widely used in the food and feed industry. WO2010/122165A1 refers to a method for producing sour dough and baked goods having an extended shelf life by biological preservation through cofermenting selected Lactobacilli, for example, L. buchneri, L. parabuchneri and L. diolivorans. 
L. diolivorans sp. nov. (DSMZ14421, LMG19667), was identified as a 1,2-propane diol degrading bacterium and isolated from aerobically stable maize silage (Krooneman et al. International Journal of Systematic and Evolutionary Microbiology 2002, 52, 639-646).
WO2006/007395A1 and WO2007/103032A2 describe bacterial additives to (sugarcane) silage employing an inoculum including L. diolivorans, in particular to reduce the dry matter content of the silage.
Metabolic engineering through the introduction, deletion, and modification of metabolic pathways in microorganisms by using suitable recombination techniques is widely applied for the more efficient production of desired metabolites and biomolecules. Novel substances with a broad scope of applicability in the chemical industry can be obtained e.g. from metagenomic libraries and DNA sequence based approaches.
It is the objective of the present invention to provide a biotransformation process suitable for producing chemicals using complex carbon sources, such as waste material.